In a saute pan, over high heat, add the sugar, onions and water, and cook until the sugar has dissolved. Reduce the heat to medium, add the ginger, salt, balsamic, and red and rice wine vinegars. Cook until the liquid has reduced by 80 percent (1/4 cup), about 20 to 30 minutes. Remove from the heat to a bowl and stir in the wasabi paste. Refrigerate for 1 to 2 hours, allowing flavors to combine.
Put the salmon on a flat surface, and drizzle with grapeseed oil. Combine the ginger, panko, and salt and pepper, to taste, in a small bowl. Generously sprinkle the tops of the salmon with the panko crust, spreading evenly. Add the remaining grapeseed oil to a large saute pan and when smoking, put the salmon into pan, crusted side down. Turn the heat off and allow the crust to brown, 1 to 2 minutes. Remove the salmon from the pan to a cutting board.
With a sharp knife, slice the salmon from top to bottom on a bias, 20 degree angle, then portion pickled onion onto serving plates. Top with sliced salmon and garnish with chives.